Catalytic article and methods of manufacturing and using the same

Abstract

The present invention provides a catalytic article comprising a) a first layer comprising a nickel component and a copper component supported on a ceria component, wherein the amount of the nickel component is 0.1 to 30 wt. %, calculated as nickel oxide, based on the total weight of the first layer, and wherein the amount of the copper component is 0.01 to 5.0 wt. % calculated as copper oxide, based on the total weight of the first layer; b) a second layer comprising a platinum group metal component supported on at least one of an oxygen storage component, an alumina component and a zirconia component, wherein the platinum group metal component comprises platinum, rhodium, palladium, or any combination thereof, and wherein the amount of the platinum group metal component is 0.01 to 5.0 wt. % based on the total weight of the second layer; and c) a substrate, wherein the first layer and the second layer are separated by a barrier layer or a gap.

The invention claimed is: 
     
       1. A catalytic article comprising:
 a) a first layer comprising a nickel component and a copper component supported on a ceria component, wherein the amount of the nickel component ranges from 0.1 wt. % to 30 wt. %, calculated as nickel oxide, based on the total weight of the first layer, and wherein the amount of the copper component ranges from 0.01 wt. % to 5.0 wt. % calculated as copper oxide, based on the total weight of the first layer; 
 b) a second layer comprising a platinum group metal component supported on one or more of an oxygen storage component, an alumina component, and a zirconia component, wherein the platinum group metal component is chosen from platinum, rhodium, palladium, and any combination thereof, and wherein the amount of the platinum group metal component ranges from 0.01 wt. % to 5.0 wt. % based on the total weight of the second layer; and 
 c) a substrate, 
 wherein the first layer and the second layer are separated by a barrier layer, and the barrier layer comprises alumina and the amount of loading of alumina in the barrier layer ranges from 0.25 g/in 3  to 3.0 g/in 3 . 
 
     
     
       2. The catalytic article according to  claim 1 , wherein the barrier layer further includes ceria, zirconia, ceria-zirconia composite, titania, and combinations thereof, wherein the barrier layer is substantially free from platinum group metals and non-PGM metals, and wherein the amount of each of the platinum group metals and non-PGM metals ranges from less than 0.001% w/w. 
     
     
       3. The catalytic article according to  claim 1 , wherein:
 the first layer is deposited as a bottom layer on a substrate; 
 the barrier layer is deposited as a middle layer on the first layer; and 
 the second layer is deposited as a top layer on the middle layer. 
 
     
     
       4. The catalytic article according to  claim 2 , wherein the amount of loading of alumina in the barrier layer ranges from 0.5 g/in 3  to 2.0 g/in 3 . 
     
     
       5. The catalytic article according to  claim 1 , wherein the amount of the nickel component ranges from 5.0 wt. % to 15 wt. %, calculated as nickel oxide, based on the total weight of the first layer and the amount of the copper component ranges from 0.25 wt. % to 1.0 wt. %, based on the total weight of the first layer. 
     
     
       6. The catalytic article according to  claim 1 , wherein the barrier layer further comprises a dopant for alumina chosen from barium, strontium, calcium, magnesium, and lanthanum. 
     
     
       7. The catalytic article according to  claim 1 , wherein the first layer further comprises a non-PGM metal chosen from manganese, vanadium, cobalt, tungsten, and molybdenum. 
     
     
       8. The catalytic article according to  claim 1 , wherein the nickel component comprises a water soluble or water insoluble nickel compound chosen from nickel nitrate, nickel acetate, nickel carbonate, nickel sulfate, nickel oxide and any combination thereof. 
     
     
       9. The catalytic article according to  claim 1 , wherein the copper component comprises a water soluble or water insoluble copper compound chosen from copper metal, copper oxide, copper hydroxide, copper acetate, copper nitrate, copper sulfate, copper carbonate, copper acetylacetonate and any combination thereof. 
     
     
       10. The catalytic article according to  claim 1 , wherein the ceria component comprises ceria having a specific surface area ranging from 15 m 2 /g to 60 m 2 /g after calcination at 950° C. for 12 hours in the air, and the amount of the ceria component ranges from 20 wt. % to 80 wt. % based on the total weight of the first layer. 
     
     
       11. The catalytic article according to  claim 1 , wherein the ceria component of the first layer further comprises a dopant chosen from zirconia, yttria, praseodymia, lanthana, neodymia, samaria, gadolinia, alumina, titania, baria, strontia, and combinations thereof, and wherein the amount of the dopant ranges from 1.0 wt. % to 20 wt. % based on the total weight of the ceria component. 
     
     
       12. The catalytic article according to  claim 1 , wherein the amount of the platinum group metal component in the second layer ranges from 0.02 wt. % to 1.0 wt. % based on the total weight of the second layer. 
     
     
       13. The catalytic article according to  claim 1 , wherein the oxygen storage component is chosen from ceria-zirconia, ceria-zirconia-lanthana, ceria-zirconia-yttria, ceria-zirconia-lanthana-yttria, ceria-zirconia-neodymia, ceria-zirconia-praseodymia, ceria-zirconia-lanthana-neodymia, ceria-zirconia-lanthana-praseodymia, ceria-zirconia-lanthana-neodymia-praseodymia, and any combination thereof, and wherein the amount of the oxygen storage component ranges from 20 wt. % to 80 wt. % based on the total weight of the second layer. 
     
     
       14. The catalytic article according to  claim 1 , wherein the alumina component is chosen from alumina, lanthana-alumina, ceria-alumina, ceria-zirconia-alumina, zirconia-alumina, lanthana-zirconia-alumina, baria-alumina, baria-lanthana-alumina, baria-lanthana-neodymia-alumina, and combinations thereof; and wherein the amount of the alumina component ranges from 10 wt. % to 80 wt. % based on the total weight of the second layer. 
     
     
       15. The catalytic article according to  claim 14 , wherein the ceria content of the oxygen storage component in the second layer ranges from 5.0 wt. % to 50 wt. % based on the total weight of the oxygen storage component. 
     
     
       16. The catalytic article according to  claim 1 , wherein the substrate is chosen from ceramic substrate, metal substrate, ceramic foam substrate, polymer foam substrate, and woven fibre substrate. 
     
     
       17. The catalytic article according to  claim 1 , wherein at least one of the first and second layer comprises a first zone or a second zone, and wherein the first or second zone covers from 30% to 90% of the length of the substrate. 
     
     
       18. The catalytic article according to  claim 1 , wherein the first or the second layer is deposited as a top layer or bottom layer on the substrate. 
     
     
       19. A process for the preparation of a catalytic article according to  claim 1 , comprising:
 preparing a first layer slurry; 
 depositing the first layer slurry on a substrate to obtain a first layer; 
 preparing a barrier layer slurry and depositing the barrier layer slurry as a middle layer on the first layer; 
 preparing a second layer slurry; and 
 depositing the second layer slurry on the middle layer to obtain a second layer followed by calcination at a temperature ranging from 400° C. to 700° C., 
 wherein the step of preparing the first layer slurry or second layer slurry comprises a technique chosen from incipient wetness impregnation, incipient wetness co-impregnation, and post-addition. 
 
     
     
       20. A process for the preparation of a catalytic article according to  claim 1 , comprising:
 preparing a first layer slurry; 
 depositing the first layer slurry on a substrate as a second zone to obtain a first layer; 
 preparing a second layer slurry; and 
 depositing the second layer slurry on the substrate as a first zone to obtain a second layer, followed by calcination at a temperature ranging from 400° C. to 700° C., 
 wherein the first layer and the second layer are separated by a gap ranging from 1 mm to 10 mm on the substrate, and wherein the step of preparing the first layer slurry or second layer slurry comprises a technique chosen from incipient wetness impregnation, incipient wetness co-impregnation, and post-addition. 
 
     
     
       21. An exhaust system for internal combustion engines comprising i) a catalytic article according to  claim 1 ; and ii) optionally, a platinum group metal based three-way conversion (TWC) catalytic article comprising from 1 g/ft 3  to 300 g/ft 3  of a platinum group metal chosen from platinum, palladium, rhodium, and combination thereof. 
     
     
       22. The exhaust system according to  claim 21 , wherein the system comprises a platinum group metal based three-way conversion (TWC) catalytic article and a catalytic article according to  claim 1 , and wherein the platinum group metal based three-way conversion (TWC) catalytic article is positioned downstream from an internal combustion engine and the catalytic article is positioned downstream in fluid communication with the platinum group metal based three-way conversion (TWC) catalytic article. 
     
     
       23. The exhaust system according to  claim 21 , wherein the system comprises a platinum group metal based three-way conversion (TWC) catalytic article and a catalytic article according to  claim 1 , and wherein the catalytic article is positioned downstream from an internal combustion engine and the platinum group metal based three-way conversion (TWC) catalytic article is positioned downstream in fluid communication with the three-way conversion (TWC) catalytic article. 
     
     
       24. A method for reducing hydrocarbons, carbon monoxide, and nitrogen oxide levels in a gaseous exhaust stream comprising:
 contacting the gaseous exhaust stream with a catalytic article according to  claim 1  to reduce the levels of hydrocarbons, carbon monoxide, and nitrogen oxide in the exhaust gas.